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A study to evaluate the safety and effectiveness of MRNA3771 and GRNA1599 in adults with chronic hepatitis B

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This study focuses on individuals living with Chronic Hepatitis B, which is a long-term infection of the liver caused by a virus. The research aims to evaluate the safety and effectiveness of an experimental treatment known as CRMA-1001. This medication contains two specific components, MRNA3771 and GRNA1599, which are administered through an intravenous infusion, a process where the medicine is delivered directly into a vein.

The purpose of this study is to assess the safety and tolerability of single and multiple doses of the study drug. During the course of the research, participants will receive the treatment to observe how the body processes the substances and how it affects various markers of the virus. Researchers will monitor levels of HBsAg, which is a protein on the surface of the virus, and HBV DNA, which is the genetic material of the virus, to see if the treatment helps reduce the presence of the infection.

The research process

The trial runs in 2 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Administration of study medication

    The medication CRMA-1001 is administered through an intravenous infusion, which means it is delivered directly into a vein.

    The study involves receiving either a single dose or multiple doses of the medication to evaluate how the body reacts to it.

  2. Step 2

    Monitoring period

    Safety and side effects are monitored from the start of the medication through month 6.

    Additional monitoring for safety and effects continues from month 6 until the end of the study.

    Blood tests are used to track changes in HBV DNA (the virus amount), HBsAg (a surface antigen used to detect the virus), and other biomarkers (indicators of biological processes) to measure the effectiveness of the treatment.

Who can join the trial?

16 criteria

  • You must be an adult between the ages of 18 and 64 years old at the time you sign the study agreement.
  • You must have chronic Hepatitis B, which means you have had a positive test for the HBsAg (a protein on the surface of the Hepatitis B virus) for at least 6 months.
  • You must be taking a stable dose of NUC (nucleos(t)ide analogues, which are medicines used to control the Hepatitis B virus) and must plan to stay on that same medicine throughout the study.
  • Your HBV DNA (the amount of Hepatitis B virus in your blood) must be very low, specifically less than 10 IU/mL.
  • Your HBsAg levels must be 100 IU/mL or higher.
  • You must test negative for HBeAg (another protein produced by the Hepatitis B virus), unless you are part of a specific group in the study that is positive for this protein.
  • Your ALT and AST (liver enzymes that indicate liver health) must be within 1.5 times of the ULN (upper limit of normal, which is the highest range considered healthy).
  • Your total bilirubin (a yellow substance in the blood produced by the liver) must be within the ULN (upper limit of normal).
  • Your PT, INR, and aPTT (tests that measure how long it takes your blood to clot) must be within the ULN (upper limit of normal).
  • Your hemoglobin (the protein in red blood cells that carries oxygen) must be at least 10 g/dL.
  • Your platelets (cells that help your blood clot) must be at or above the LLN (lower limit of normal, which is the lowest range considered healthy).
  • Your WBC (white blood cells that fight infection) must be within the ULN (upper limit of normal) and your ANC (absolute neutrophil count, a specific type of white blood cell) must be at least 1000/µl.
  • Your eGFR (a measure of how well your kidneys filter your blood) must be 60 mL/min/1.73m2 or higher.
  • Your body weight must be between 45 kg and 150 kg.
  • Your BMI (body mass index, a measure of body fat based on height and weight) must be between 18 and 32 kg/m2.
  • You must agree to follow the contraceptive (methods used to prevent pregnancy, such as birth control) requirements listed in the study rules.

Who cannot join the trial?

10 criteria

  • Having advanced liver scarring (known as fibrosis) or permanent liver damage (known as cirrhosis), which can be measured by a specialized scan called a FibroScan or through a liver biopsy (a procedure where a small piece of liver tissue is removed for testing).
  • A history of liver failure, which might show up as ascites (fluid buildup in the belly), hepatic encephalopathy (confusion or changes in brain function due to liver problems), or varices (swollen veins in the stomach or throat).
  • Having any other liver-related conditions besides Hepatitis B, such as hemochromatosis (too much iron in the body), autoimmune hepatitis (where the immune system attacks the liver), alcoholic liver disease, or non-alcoholic steatohepatitis (fatty liver disease).
  • Having other known problems with the liver or bile ducts (the tubes that carry digestive fluid), except for Gilbert's syndrome (a harmless liver condition) or gallstones that do not cause symptoms.
  • Being infected with other viruses at the same time, such as HCV (Hepatitis C), HIV, or HDV (Hepatitis D).
  • Having a high level of AFP (a protein often used as a marker for certain types of liver cancer) above 100 ng/mL.
  • Using or needing any other systemic antiviral therapy (medicine that fights viruses throughout the entire body) during the study, except for certain common treatments for Hepatitis B or HSV (herpes virus).
  • Having abnormal results from an ECG (a test that records the electrical activity of the heart), such as arrhythmias (irregular heartbeats) or QT abnormalities (a delay in the heart's electrical recharging system).
  • Having known risks for a dangerous heart rhythm called Torsade de Pointes, such as hypokalemia (low potassium levels) or heart failure, or a history of congenital long QT syndrome (a heart rhythm problem present from birth).
  • Being pregnant or breastfeeding, or planning to become pregnant or breastfeed within 2 years of taking the study medication.
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Investigated drugs

CRMA-1001 is an experimental therapy delivered through an intravenous infusion. It is being studied to see if it can help treat adults living with chronic hepatitis B by targeting the virus.

What is already known about the treatment

CRMA-1001 - This experimental treatment is given through an intravenous infusion, which means it is delivered directly into a vein. It consists of two genetic components, mRNA3771 and GRNA1599, that are currently being studied in clinical trials to treat chronic hepatitis B. This medication works at a molecular level by using genetic instructions to help the body recognize and fight the virus that causes the infection. It is classified as a genetic-based therapy designed to target the underlying cause of the disease.

Investigated diseases

Chronic Hepatitis B - This is a long-term infection caused by the hepatitis B virus that persists in the body for more than six months. The virus targets the liver, leading to ongoing inflammation and damage to liver cells. Over time, the immune system may struggle to clear the virus, allowing it to remain active. The condition can progress through different stages, often involving changes in the levels of viral proteins and genetic material in the blood. Persistent infection can lead to structural changes in the liver tissue.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase I/IITrial ID2025-523619-12-00Protocol codeCRMA-1001-101Estimated enrolment66 patientsSponsorNchroma Bio Inc.

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).